From: Jason Lunz Date: Sat, 1 Sep 2007 19:06:03 +0000 (-0700) Subject: [JFFS2] fix write deadlock regression X-Git-Tag: v2.6.23-rc6~26^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fc0e01974ccccc7530b7634a63ee3fcc57b845ea;p=pandora-kernel.git [JFFS2] fix write deadlock regression I've bisected the deadlock when many small appends are done on jffs2 down to this commit: commit 6fe6900e1e5b6fa9e5c59aa5061f244fe3f467e2 Author: Nick Piggin Date: Sun May 6 14:49:04 2007 -0700 mm: make read_cache_page synchronous Ensure pages are uptodate after returning from read_cache_page, which allows us to cut out most of the filesystem-internal PageUptodate calls. I didn't have a great look down the call chains, but this appears to fixes 7 possible use-before uptodate in hfs, 2 in hfsplus, 1 in jfs, a few in ecryptfs, 1 in jffs2, and a possible cleared data overwritten with readpage in block2mtd. All depending on whether the filler is async and/or can return with a !uptodate page. It introduced a wait to read_cache_page, as well as a read_cache_page_async function equivalent to the old read_cache_page without any callers. Switching jffs2_gc_fetch_page to read_cache_page_async for the old behavior makes the deadlocks go away, but maybe reintroduces the use-before-uptodate problem? I don't understand the mm/fs interaction well enough to say. [It's fine. dwmw2.] Signed-off-by: Jason Lunz Signed-off-by: David Woodhouse --- Reading git-diff-tree failed